package com.star.common.utils;

import org.springframework.util.StringUtils;

import javax.servlet.http.HttpServletRequest;

public class IpUtils {
    private IpUtils() {
    }

    public static final String DEFAULT_IP = "0:0:0:0:0:0:0:1"; //默认ip地址

    private static final String X_REAL_IP = "X-REAL-IP";

    private static final String X_FORWARDED_FOR = "X-Forwarded-For";

    public static String getIpAddr(HttpServletRequest request) {
        String realIp = request.getHeader(X_REAL_IP);
        String xForwarded = request.getHeader(X_FORWARDED_FOR);
        String remoteAddr = request.getRemoteAddr();
        String ip = "";
        if (StringUtils.hasText(xForwarded)) { // 代表可能存在多台nginx
            String[] ips = xForwarded.split(",");
            ip = ips[0];
        } else if (StringUtils.hasText(realIp)) {
            ip = realIp;
        } else {
            ip = remoteAddr;
        }
        return ip;
    }

    public static String getIPAddress(HttpServletRequest request) {
        String ip = null;
        //X-Forwarded-For：Squid 服务代理
        String ipAddresses = request.getHeader("X-Forwarded-For");
        if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
            //Proxy-Client-IP：apache 服务代理
            ipAddresses = request.getHeader("Proxy-Client-IP");
        }
        if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
            //WL-Proxy-Client-IP：weblogic 服务代理
            ipAddresses = request.getHeader("WL-Proxy-Client-IP");
        }
        if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
            //HTTP_CLIENT_IP：有些代理服务器
            ipAddresses = request.getHeader("HTTP_CLIENT_IP");
        }
        if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
            //X-Real-IP：nginx服务代理
            ipAddresses = request.getHeader("X-Real-IP");
        }
        //有些网络通过多层代理，那么获取到的ip就会有多个，一般都是通过逗号（,）分割开来，并且第一个ip为客户端的真实IP
        if (ipAddresses != null && ipAddresses.length() != 0) {
            ip = ipAddresses.split(",")[0];
        }
        //还是不能获取到，最后再通过request.getRemoteAddr();获取
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
            ip = request.getRemoteAddr();
        }
        return ip;
    }

}
